noun
phi
feye
noun
1
The 21st letter of the Greek alphabet (Φ, φ), often used as a symbol in science and mathematics.
"In the equation, phi represents the phase angle."
2
The golden ratio, approximately 1.618, often represented by this letter.
"The proportions of the building were designed around phi."
How to Use Phi
Learner’s notesIn plain EnglishA Greek letter, commonly used as shorthand for the golden ratio in math and design.
Word Forms
phis plural
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In the equation, _____ represents the phase angle.
Etymology
From the Greek letter phei, borrowed into Latin and then English as "phi."